+++ /dev/null
-/***************************************************************************/
-/* */
-/* ftstroke.c */
-/* */
-/* FreeType path stroker (body). */
-/* */
-/* Copyright 2002-2017 by */
-/* David Turner, Robert Wilhelm, and Werner Lemberg. */
-/* */
-/* This file is part of the FreeType project, and may only be used, */
-/* modified, and distributed under the terms of the FreeType project */
-/* license, LICENSE.TXT. By continuing to use, modify, or distribute */
-/* this file you indicate that you have read the license and */
-/* understand and accept it fully. */
-/* */
-/***************************************************************************/
-
-
-#include <ft2build.h>
-#include FT_STROKER_H
-#include FT_TRIGONOMETRY_H
-#include FT_OUTLINE_H
-#include FT_INTERNAL_MEMORY_H
-#include FT_INTERNAL_DEBUG_H
-#include FT_INTERNAL_OBJECTS_H
-
-#include "basepic.h"
-
-
- /* declare an extern to access `ft_outline_glyph_class' globally */
- /* allocated in `ftglyph.c', and use the FT_OUTLINE_GLYPH_CLASS_GET */
- /* macro to access it when FT_CONFIG_OPTION_PIC is defined */
-#ifndef FT_CONFIG_OPTION_PIC
- FT_CALLBACK_TABLE const FT_Glyph_Class ft_outline_glyph_class;
-#endif
-
-
- /* documentation is in ftstroke.h */
-
- FT_EXPORT_DEF( FT_StrokerBorder )
- FT_Outline_GetInsideBorder( FT_Outline* outline )
- {
- FT_Orientation o = FT_Outline_Get_Orientation( outline );
-
-
- return o == FT_ORIENTATION_TRUETYPE ? FT_STROKER_BORDER_RIGHT
- : FT_STROKER_BORDER_LEFT;
- }
-
-
- /* documentation is in ftstroke.h */
-
- FT_EXPORT_DEF( FT_StrokerBorder )
- FT_Outline_GetOutsideBorder( FT_Outline* outline )
- {
- FT_Orientation o = FT_Outline_Get_Orientation( outline );
-
-
- return o == FT_ORIENTATION_TRUETYPE ? FT_STROKER_BORDER_LEFT
- : FT_STROKER_BORDER_RIGHT;
- }
-
-
- /*************************************************************************/
- /*************************************************************************/
- /***** *****/
- /***** BEZIER COMPUTATIONS *****/
- /***** *****/
- /*************************************************************************/
- /*************************************************************************/
-
-#define FT_SMALL_CONIC_THRESHOLD ( FT_ANGLE_PI / 6 )
-#define FT_SMALL_CUBIC_THRESHOLD ( FT_ANGLE_PI / 8 )
-
-#define FT_EPSILON 2
-
-#define FT_IS_SMALL( x ) ( (x) > -FT_EPSILON && (x) < FT_EPSILON )
-
-
- static FT_Pos
- ft_pos_abs( FT_Pos x )
- {
- return x >= 0 ? x : -x;
- }
-
-
- static void
- ft_conic_split( FT_Vector* base )
- {
- FT_Pos a, b;
-
-
- base[4].x = base[2].x;
- b = base[1].x;
- a = base[3].x = ( base[2].x + b ) / 2;
- b = base[1].x = ( base[0].x + b ) / 2;
- base[2].x = ( a + b ) / 2;
-
- base[4].y = base[2].y;
- b = base[1].y;
- a = base[3].y = ( base[2].y + b ) / 2;
- b = base[1].y = ( base[0].y + b ) / 2;
- base[2].y = ( a + b ) / 2;
- }
-
-
- static FT_Bool
- ft_conic_is_small_enough( FT_Vector* base,
- FT_Angle *angle_in,
- FT_Angle *angle_out )
- {
- FT_Vector d1, d2;
- FT_Angle theta;
- FT_Int close1, close2;
-
-
- d1.x = base[1].x - base[2].x;
- d1.y = base[1].y - base[2].y;
- d2.x = base[0].x - base[1].x;
- d2.y = base[0].y - base[1].y;
-
- close1 = FT_IS_SMALL( d1.x ) && FT_IS_SMALL( d1.y );
- close2 = FT_IS_SMALL( d2.x ) && FT_IS_SMALL( d2.y );
-
- if ( close1 )
- {
- if ( close2 )
- {
- /* basically a point; */
- /* do nothing to retain original direction */
- }
- else
- {
- *angle_in =
- *angle_out = FT_Atan2( d2.x, d2.y );
- }
- }
- else /* !close1 */
- {
- if ( close2 )
- {
- *angle_in =
- *angle_out = FT_Atan2( d1.x, d1.y );
- }
- else
- {
- *angle_in = FT_Atan2( d1.x, d1.y );
- *angle_out = FT_Atan2( d2.x, d2.y );
- }
- }
-
- theta = ft_pos_abs( FT_Angle_Diff( *angle_in, *angle_out ) );
-
- return FT_BOOL( theta < FT_SMALL_CONIC_THRESHOLD );
- }
-
-
- static void
- ft_cubic_split( FT_Vector* base )
- {
- FT_Pos a, b, c, d;
-
-
- base[6].x = base[3].x;
- c = base[1].x;
- d = base[2].x;
- base[1].x = a = ( base[0].x + c ) / 2;
- base[5].x = b = ( base[3].x + d ) / 2;
- c = ( c + d ) / 2;
- base[2].x = a = ( a + c ) / 2;
- base[4].x = b = ( b + c ) / 2;
- base[3].x = ( a + b ) / 2;
-
- base[6].y = base[3].y;
- c = base[1].y;
- d = base[2].y;
- base[1].y = a = ( base[0].y + c ) / 2;
- base[5].y = b = ( base[3].y + d ) / 2;
- c = ( c + d ) / 2;
- base[2].y = a = ( a + c ) / 2;
- base[4].y = b = ( b + c ) / 2;
- base[3].y = ( a + b ) / 2;
- }
-
-
- /* Return the average of `angle1' and `angle2'. */
- /* This gives correct result even if `angle1' and `angle2' */
- /* have opposite signs. */
- static FT_Angle
- ft_angle_mean( FT_Angle angle1,
- FT_Angle angle2 )
- {
- return angle1 + FT_Angle_Diff( angle1, angle2 ) / 2;
- }
-
-
- static FT_Bool
- ft_cubic_is_small_enough( FT_Vector* base,
- FT_Angle *angle_in,
- FT_Angle *angle_mid,
- FT_Angle *angle_out )
- {
- FT_Vector d1, d2, d3;
- FT_Angle theta1, theta2;
- FT_Int close1, close2, close3;
-
-
- d1.x = base[2].x - base[3].x;
- d1.y = base[2].y - base[3].y;
- d2.x = base[1].x - base[2].x;
- d2.y = base[1].y - base[2].y;
- d3.x = base[0].x - base[1].x;
- d3.y = base[0].y - base[1].y;
-
- close1 = FT_IS_SMALL( d1.x ) && FT_IS_SMALL( d1.y );
- close2 = FT_IS_SMALL( d2.x ) && FT_IS_SMALL( d2.y );
- close3 = FT_IS_SMALL( d3.x ) && FT_IS_SMALL( d3.y );
-
- if ( close1 )
- {
- if ( close2 )
- {
- if ( close3 )
- {
- /* basically a point; */
- /* do nothing to retain original direction */
- }
- else /* !close3 */
- {
- *angle_in =
- *angle_mid =
- *angle_out = FT_Atan2( d3.x, d3.y );
- }
- }
- else /* !close2 */
- {
- if ( close3 )
- {
- *angle_in =
- *angle_mid =
- *angle_out = FT_Atan2( d2.x, d2.y );
- }
- else /* !close3 */
- {
- *angle_in =
- *angle_mid = FT_Atan2( d2.x, d2.y );
- *angle_out = FT_Atan2( d3.x, d3.y );
- }
- }
- }
- else /* !close1 */
- {
- if ( close2 )
- {
- if ( close3 )
- {
- *angle_in =
- *angle_mid =
- *angle_out = FT_Atan2( d1.x, d1.y );
- }
- else /* !close3 */
- {
- *angle_in = FT_Atan2( d1.x, d1.y );
- *angle_out = FT_Atan2( d3.x, d3.y );
- *angle_mid = ft_angle_mean( *angle_in, *angle_out );
- }
- }
- else /* !close2 */
- {
- if ( close3 )
- {
- *angle_in = FT_Atan2( d1.x, d1.y );
- *angle_mid =
- *angle_out = FT_Atan2( d2.x, d2.y );
- }
- else /* !close3 */
- {
- *angle_in = FT_Atan2( d1.x, d1.y );
- *angle_mid = FT_Atan2( d2.x, d2.y );
- *angle_out = FT_Atan2( d3.x, d3.y );
- }
- }
- }
-
- theta1 = ft_pos_abs( FT_Angle_Diff( *angle_in, *angle_mid ) );
- theta2 = ft_pos_abs( FT_Angle_Diff( *angle_mid, *angle_out ) );
-
- return FT_BOOL( theta1 < FT_SMALL_CUBIC_THRESHOLD &&
- theta2 < FT_SMALL_CUBIC_THRESHOLD );
- }
-
-
- /*************************************************************************/
- /*************************************************************************/
- /***** *****/
- /***** STROKE BORDERS *****/
- /***** *****/
- /*************************************************************************/
- /*************************************************************************/
-
- typedef enum FT_StrokeTags_
- {
- FT_STROKE_TAG_ON = 1, /* on-curve point */
- FT_STROKE_TAG_CUBIC = 2, /* cubic off-point */
- FT_STROKE_TAG_BEGIN = 4, /* sub-path start */
- FT_STROKE_TAG_END = 8 /* sub-path end */
-
- } FT_StrokeTags;
-
-#define FT_STROKE_TAG_BEGIN_END ( FT_STROKE_TAG_BEGIN | FT_STROKE_TAG_END )
-
- typedef struct FT_StrokeBorderRec_
- {
- FT_UInt num_points;
- FT_UInt max_points;
- FT_Vector* points;
- FT_Byte* tags;
- FT_Bool movable; /* TRUE for ends of lineto borders */
- FT_Int start; /* index of current sub-path start point */
- FT_Memory memory;
- FT_Bool valid;
-
- } FT_StrokeBorderRec, *FT_StrokeBorder;
-
-
- static FT_Error
- ft_stroke_border_grow( FT_StrokeBorder border,
- FT_UInt new_points )
- {
- FT_UInt old_max = border->max_points;
- FT_UInt new_max = border->num_points + new_points;
- FT_Error error = FT_Err_Ok;
-
-
- if ( new_max > old_max )
- {
- FT_UInt cur_max = old_max;
- FT_Memory memory = border->memory;
-
-
- while ( cur_max < new_max )
- cur_max += ( cur_max >> 1 ) + 16;
-
- if ( FT_RENEW_ARRAY( border->points, old_max, cur_max ) ||
- FT_RENEW_ARRAY( border->tags, old_max, cur_max ) )
- goto Exit;
-
- border->max_points = cur_max;
- }
-
- Exit:
- return error;
- }
-
-
- static void
- ft_stroke_border_close( FT_StrokeBorder border,
- FT_Bool reverse )
- {
- FT_UInt start = (FT_UInt)border->start;
- FT_UInt count = border->num_points;
-
-
- FT_ASSERT( border->start >= 0 );
-
- /* don't record empty paths! */
- if ( count <= start + 1U )
- border->num_points = start;
- else
- {
- /* copy the last point to the start of this sub-path, since */
- /* it contains the `adjusted' starting coordinates */
- border->num_points = --count;
- border->points[start] = border->points[count];
-
- if ( reverse )
- {
- /* reverse the points */
- {
- FT_Vector* vec1 = border->points + start + 1;
- FT_Vector* vec2 = border->points + count - 1;
-
-
- for ( ; vec1 < vec2; vec1++, vec2-- )
- {
- FT_Vector tmp;
-
-
- tmp = *vec1;
- *vec1 = *vec2;
- *vec2 = tmp;
- }
- }
-
- /* then the tags */
- {
- FT_Byte* tag1 = border->tags + start + 1;
- FT_Byte* tag2 = border->tags + count - 1;
-
-
- for ( ; tag1 < tag2; tag1++, tag2-- )
- {
- FT_Byte tmp;
-
-
- tmp = *tag1;
- *tag1 = *tag2;
- *tag2 = tmp;
- }
- }
- }
-
- border->tags[start ] |= FT_STROKE_TAG_BEGIN;
- border->tags[count - 1] |= FT_STROKE_TAG_END;
- }
-
- border->start = -1;
- border->movable = FALSE;
- }
-
-
- static FT_Error
- ft_stroke_border_lineto( FT_StrokeBorder border,
- FT_Vector* to,
- FT_Bool movable )
- {
- FT_Error error = FT_Err_Ok;
-
-
- FT_ASSERT( border->start >= 0 );
-
- if ( border->movable )
- {
- /* move last point */
- border->points[border->num_points - 1] = *to;
- }
- else
- {
- /* don't add zero-length lineto */
- if ( border->num_points > 0 &&
- FT_IS_SMALL( border->points[border->num_points - 1].x - to->x ) &&
- FT_IS_SMALL( border->points[border->num_points - 1].y - to->y ) )
- return error;
-
- /* add one point */
- error = ft_stroke_border_grow( border, 1 );
- if ( !error )
- {
- FT_Vector* vec = border->points + border->num_points;
- FT_Byte* tag = border->tags + border->num_points;
-
-
- vec[0] = *to;
- tag[0] = FT_STROKE_TAG_ON;
-
- border->num_points += 1;
- }
- }
- border->movable = movable;
- return error;
- }
-
-
- static FT_Error
- ft_stroke_border_conicto( FT_StrokeBorder border,
- FT_Vector* control,
- FT_Vector* to )
- {
- FT_Error error;
-
-
- FT_ASSERT( border->start >= 0 );
-
- error = ft_stroke_border_grow( border, 2 );
- if ( !error )
- {
- FT_Vector* vec = border->points + border->num_points;
- FT_Byte* tag = border->tags + border->num_points;
-
-
- vec[0] = *control;
- vec[1] = *to;
-
- tag[0] = 0;
- tag[1] = FT_STROKE_TAG_ON;
-
- border->num_points += 2;
- }
-
- border->movable = FALSE;
-
- return error;
- }
-
-
- static FT_Error
- ft_stroke_border_cubicto( FT_StrokeBorder border,
- FT_Vector* control1,
- FT_Vector* control2,
- FT_Vector* to )
- {
- FT_Error error;
-
-
- FT_ASSERT( border->start >= 0 );
-
- error = ft_stroke_border_grow( border, 3 );
- if ( !error )
- {
- FT_Vector* vec = border->points + border->num_points;
- FT_Byte* tag = border->tags + border->num_points;
-
-
- vec[0] = *control1;
- vec[1] = *control2;
- vec[2] = *to;
-
- tag[0] = FT_STROKE_TAG_CUBIC;
- tag[1] = FT_STROKE_TAG_CUBIC;
- tag[2] = FT_STROKE_TAG_ON;
-
- border->num_points += 3;
- }
-
- border->movable = FALSE;
-
- return error;
- }
-
-
-#define FT_ARC_CUBIC_ANGLE ( FT_ANGLE_PI / 2 )
-
-
- static FT_Error
- ft_stroke_border_arcto( FT_StrokeBorder border,
- FT_Vector* center,
- FT_Fixed radius,
- FT_Angle angle_start,
- FT_Angle angle_diff )
- {
- FT_Angle total, angle, step, rotate, next, theta;
- FT_Vector a, b, a2, b2;
- FT_Fixed length;
- FT_Error error = FT_Err_Ok;
-
-
- /* compute start point */
- FT_Vector_From_Polar( &a, radius, angle_start );
- a.x += center->x;
- a.y += center->y;
-
- total = angle_diff;
- angle = angle_start;
- rotate = ( angle_diff >= 0 ) ? FT_ANGLE_PI2 : -FT_ANGLE_PI2;
-
- while ( total != 0 )
- {
- step = total;
- if ( step > FT_ARC_CUBIC_ANGLE )
- step = FT_ARC_CUBIC_ANGLE;
-
- else if ( step < -FT_ARC_CUBIC_ANGLE )
- step = -FT_ARC_CUBIC_ANGLE;
-
- next = angle + step;
- theta = step;
- if ( theta < 0 )
- theta = -theta;
-
- theta >>= 1;
-
- /* compute end point */
- FT_Vector_From_Polar( &b, radius, next );
- b.x += center->x;
- b.y += center->y;
-
- /* compute first and second control points */
- length = FT_MulDiv( radius, FT_Sin( theta ) * 4,
- ( 0x10000L + FT_Cos( theta ) ) * 3 );
-
- FT_Vector_From_Polar( &a2, length, angle + rotate );
- a2.x += a.x;
- a2.y += a.y;
-
- FT_Vector_From_Polar( &b2, length, next - rotate );
- b2.x += b.x;
- b2.y += b.y;
-
- /* add cubic arc */
- error = ft_stroke_border_cubicto( border, &a2, &b2, &b );
- if ( error )
- break;
-
- /* process the rest of the arc ?? */
- a = b;
- total -= step;
- angle = next;
- }
-
- return error;
- }
-
-
- static FT_Error
- ft_stroke_border_moveto( FT_StrokeBorder border,
- FT_Vector* to )
- {
- /* close current open path if any ? */
- if ( border->start >= 0 )
- ft_stroke_border_close( border, FALSE );
-
- border->start = (FT_Int)border->num_points;
- border->movable = FALSE;
-
- return ft_stroke_border_lineto( border, to, FALSE );
- }
-
-
- static void
- ft_stroke_border_init( FT_StrokeBorder border,
- FT_Memory memory )
- {
- border->memory = memory;
- border->points = NULL;
- border->tags = NULL;
-
- border->num_points = 0;
- border->max_points = 0;
- border->start = -1;
- border->valid = FALSE;
- }
-
-
- static void
- ft_stroke_border_reset( FT_StrokeBorder border )
- {
- border->num_points = 0;
- border->start = -1;
- border->valid = FALSE;
- }
-
-
- static void
- ft_stroke_border_done( FT_StrokeBorder border )
- {
- FT_Memory memory = border->memory;
-
-
- FT_FREE( border->points );
- FT_FREE( border->tags );
-
- border->num_points = 0;
- border->max_points = 0;
- border->start = -1;
- border->valid = FALSE;
- }
-
-
- static FT_Error
- ft_stroke_border_get_counts( FT_StrokeBorder border,
- FT_UInt *anum_points,
- FT_UInt *anum_contours )
- {
- FT_Error error = FT_Err_Ok;
- FT_UInt num_points = 0;
- FT_UInt num_contours = 0;
-
- FT_UInt count = border->num_points;
- FT_Vector* point = border->points;
- FT_Byte* tags = border->tags;
- FT_Int in_contour = 0;
-
-
- for ( ; count > 0; count--, num_points++, point++, tags++ )
- {
- if ( tags[0] & FT_STROKE_TAG_BEGIN )
- {
- if ( in_contour != 0 )
- goto Fail;
-
- in_contour = 1;
- }
- else if ( in_contour == 0 )
- goto Fail;
-
- if ( tags[0] & FT_STROKE_TAG_END )
- {
- in_contour = 0;
- num_contours++;
- }
- }
-
- if ( in_contour != 0 )
- goto Fail;
-
- border->valid = TRUE;
-
- Exit:
- *anum_points = num_points;
- *anum_contours = num_contours;
- return error;
-
- Fail:
- num_points = 0;
- num_contours = 0;
- goto Exit;
- }
-
-
- static void
- ft_stroke_border_export( FT_StrokeBorder border,
- FT_Outline* outline )
- {
- /* copy point locations */
- if ( border->num_points )
- FT_ARRAY_COPY( outline->points + outline->n_points,
- border->points,
- border->num_points );
-
- /* copy tags */
- {
- FT_UInt count = border->num_points;
- FT_Byte* read = border->tags;
- FT_Byte* write = (FT_Byte*)outline->tags + outline->n_points;
-
-
- for ( ; count > 0; count--, read++, write++ )
- {
- if ( *read & FT_STROKE_TAG_ON )
- *write = FT_CURVE_TAG_ON;
- else if ( *read & FT_STROKE_TAG_CUBIC )
- *write = FT_CURVE_TAG_CUBIC;
- else
- *write = FT_CURVE_TAG_CONIC;
- }
- }
-
- /* copy contours */
- {
- FT_UInt count = border->num_points;
- FT_Byte* tags = border->tags;
- FT_Short* write = outline->contours + outline->n_contours;
- FT_Short idx = (FT_Short)outline->n_points;
-
-
- for ( ; count > 0; count--, tags++, idx++ )
- {
- if ( *tags & FT_STROKE_TAG_END )
- {
- *write++ = idx;
- outline->n_contours++;
- }
- }
- }
-
- outline->n_points += (short)border->num_points;
-
- FT_ASSERT( FT_Outline_Check( outline ) == 0 );
- }
-
-
- /*************************************************************************/
- /*************************************************************************/
- /***** *****/
- /***** STROKER *****/
- /***** *****/
- /*************************************************************************/
- /*************************************************************************/
-
-#define FT_SIDE_TO_ROTATE( s ) ( FT_ANGLE_PI2 - (s) * FT_ANGLE_PI )
-
- typedef struct FT_StrokerRec_
- {
- FT_Angle angle_in; /* direction into curr join */
- FT_Angle angle_out; /* direction out of join */
- FT_Vector center; /* current position */
- FT_Fixed line_length; /* length of last lineto */
- FT_Bool first_point; /* is this the start? */
- FT_Bool subpath_open; /* is the subpath open? */
- FT_Angle subpath_angle; /* subpath start direction */
- FT_Vector subpath_start; /* subpath start position */
- FT_Fixed subpath_line_length; /* subpath start lineto len */
- FT_Bool handle_wide_strokes; /* use wide strokes logic? */
-
- FT_Stroker_LineCap line_cap;
- FT_Stroker_LineJoin line_join;
- FT_Stroker_LineJoin line_join_saved;
- FT_Fixed miter_limit;
- FT_Fixed radius;
-
- FT_StrokeBorderRec borders[2];
- FT_Library library;
-
- } FT_StrokerRec;
-
-
- /* documentation is in ftstroke.h */
-
- FT_EXPORT_DEF( FT_Error )
- FT_Stroker_New( FT_Library library,
- FT_Stroker *astroker )
- {
- FT_Error error; /* assigned in FT_NEW */
- FT_Memory memory;
- FT_Stroker stroker = NULL;
-
-
- if ( !library )
- return FT_THROW( Invalid_Library_Handle );
-
- if ( !astroker )
- return FT_THROW( Invalid_Argument );
-
- memory = library->memory;
-
- if ( !FT_NEW( stroker ) )
- {
- stroker->library = library;
-
- ft_stroke_border_init( &stroker->borders[0], memory );
- ft_stroke_border_init( &stroker->borders[1], memory );
- }
-
- *astroker = stroker;
-
- return error;
- }
-
-
- /* documentation is in ftstroke.h */
-
- FT_EXPORT_DEF( void )
- FT_Stroker_Set( FT_Stroker stroker,
- FT_Fixed radius,
- FT_Stroker_LineCap line_cap,
- FT_Stroker_LineJoin line_join,
- FT_Fixed miter_limit )
- {
- if ( !stroker )
- return;
-
- stroker->radius = radius;
- stroker->line_cap = line_cap;
- stroker->line_join = line_join;
- stroker->miter_limit = miter_limit;
-
- /* ensure miter limit has sensible value */
- if ( stroker->miter_limit < 0x10000L )
- stroker->miter_limit = 0x10000L;
-
- /* save line join style: */
- /* line join style can be temporarily changed when stroking curves */
- stroker->line_join_saved = line_join;
-
- FT_Stroker_Rewind( stroker );
- }
-
-
- /* documentation is in ftstroke.h */
-
- FT_EXPORT_DEF( void )
- FT_Stroker_Rewind( FT_Stroker stroker )
- {
- if ( stroker )
- {
- ft_stroke_border_reset( &stroker->borders[0] );
- ft_stroke_border_reset( &stroker->borders[1] );
- }
- }
-
-
- /* documentation is in ftstroke.h */
-
- FT_EXPORT_DEF( void )
- FT_Stroker_Done( FT_Stroker stroker )
- {
- if ( stroker )
- {
- FT_Memory memory = stroker->library->memory;
-
-
- ft_stroke_border_done( &stroker->borders[0] );
- ft_stroke_border_done( &stroker->borders[1] );
-
- stroker->library = NULL;
- FT_FREE( stroker );
- }
- }
-
-
- /* create a circular arc at a corner or cap */
- static FT_Error
- ft_stroker_arcto( FT_Stroker stroker,
- FT_Int side )
- {
- FT_Angle total, rotate;
- FT_Fixed radius = stroker->radius;
- FT_Error error = FT_Err_Ok;
- FT_StrokeBorder border = stroker->borders + side;
-
-
- rotate = FT_SIDE_TO_ROTATE( side );
-
- total = FT_Angle_Diff( stroker->angle_in, stroker->angle_out );
- if ( total == FT_ANGLE_PI )
- total = -rotate * 2;
-
- error = ft_stroke_border_arcto( border,
- &stroker->center,
- radius,
- stroker->angle_in + rotate,
- total );
- border->movable = FALSE;
- return error;
- }
-
-
- /* add a cap at the end of an opened path */
- static FT_Error
- ft_stroker_cap( FT_Stroker stroker,
- FT_Angle angle,
- FT_Int side )
- {
- FT_Error error = FT_Err_Ok;
-
-
- if ( stroker->line_cap == FT_STROKER_LINECAP_ROUND )
- {
- /* add a round cap */
- stroker->angle_in = angle;
- stroker->angle_out = angle + FT_ANGLE_PI;
-
- error = ft_stroker_arcto( stroker, side );
- }
- else if ( stroker->line_cap == FT_STROKER_LINECAP_SQUARE )
- {
- /* add a square cap */
- FT_Vector delta, delta2;
- FT_Angle rotate = FT_SIDE_TO_ROTATE( side );
- FT_Fixed radius = stroker->radius;
- FT_StrokeBorder border = stroker->borders + side;
-
-
- FT_Vector_From_Polar( &delta2, radius, angle + rotate );
- FT_Vector_From_Polar( &delta, radius, angle );
-
- delta.x += stroker->center.x + delta2.x;
- delta.y += stroker->center.y + delta2.y;
-
- error = ft_stroke_border_lineto( border, &delta, FALSE );
- if ( error )
- goto Exit;
-
- FT_Vector_From_Polar( &delta2, radius, angle - rotate );
- FT_Vector_From_Polar( &delta, radius, angle );
-
- delta.x += delta2.x + stroker->center.x;
- delta.y += delta2.y + stroker->center.y;
-
- error = ft_stroke_border_lineto( border, &delta, FALSE );
- }
- else if ( stroker->line_cap == FT_STROKER_LINECAP_BUTT )
- {
- /* add a butt ending */
- FT_Vector delta;
- FT_Angle rotate = FT_SIDE_TO_ROTATE( side );
- FT_Fixed radius = stroker->radius;
- FT_StrokeBorder border = stroker->borders + side;
-
-
- FT_Vector_From_Polar( &delta, radius, angle + rotate );
-
- delta.x += stroker->center.x;
- delta.y += stroker->center.y;
-
- error = ft_stroke_border_lineto( border, &delta, FALSE );
- if ( error )
- goto Exit;
-
- FT_Vector_From_Polar( &delta, radius, angle - rotate );
-
- delta.x += stroker->center.x;
- delta.y += stroker->center.y;
-
- error = ft_stroke_border_lineto( border, &delta, FALSE );
- }
-
- Exit:
- return error;
- }
-
-
- /* process an inside corner, i.e. compute intersection */
- static FT_Error
- ft_stroker_inside( FT_Stroker stroker,
- FT_Int side,
- FT_Fixed line_length )
- {
- FT_StrokeBorder border = stroker->borders + side;
- FT_Angle phi, theta, rotate;
- FT_Fixed length, thcos;
- FT_Vector delta;
- FT_Error error = FT_Err_Ok;
- FT_Bool intersect; /* use intersection of lines? */
-
-
- rotate = FT_SIDE_TO_ROTATE( side );
-
- theta = FT_Angle_Diff( stroker->angle_in, stroker->angle_out ) / 2;
-
- /* Only intersect borders if between two lineto's and both */
- /* lines are long enough (line_length is zero for curves). */
- /* Also avoid U-turns of nearly 180 degree. */
- if ( !border->movable || line_length == 0 ||
- theta > 0x59C000 || theta < -0x59C000 )
- intersect = FALSE;
- else
- {
- /* compute minimum required length of lines */
- FT_Fixed min_length = ft_pos_abs( FT_MulFix( stroker->radius,
- FT_Tan( theta ) ) );
-
-
- intersect = FT_BOOL( min_length &&
- stroker->line_length >= min_length &&
- line_length >= min_length );
- }
-
- if ( !intersect )
- {
- FT_Vector_From_Polar( &delta, stroker->radius,
- stroker->angle_out + rotate );
- delta.x += stroker->center.x;
- delta.y += stroker->center.y;
-
- border->movable = FALSE;
- }
- else
- {
- /* compute median angle */
- phi = stroker->angle_in + theta;
-
- thcos = FT_Cos( theta );
-
- length = FT_DivFix( stroker->radius, thcos );
-
- FT_Vector_From_Polar( &delta, length, phi + rotate );
- delta.x += stroker->center.x;
- delta.y += stroker->center.y;
- }
-
- error = ft_stroke_border_lineto( border, &delta, FALSE );
-
- return error;
- }
-
-
- /* process an outside corner, i.e. compute bevel/miter/round */
- static FT_Error
- ft_stroker_outside( FT_Stroker stroker,
- FT_Int side,
- FT_Fixed line_length )
- {
- FT_StrokeBorder border = stroker->borders + side;
- FT_Error error;
- FT_Angle rotate;
-
-
- if ( stroker->line_join == FT_STROKER_LINEJOIN_ROUND )
- error = ft_stroker_arcto( stroker, side );
- else
- {
- /* this is a mitered (pointed) or beveled (truncated) corner */
- FT_Fixed sigma = 0, radius = stroker->radius;
- FT_Angle theta = 0, phi = 0;
- FT_Fixed thcos = 0;
- FT_Bool bevel, fixed_bevel;
-
-
- rotate = FT_SIDE_TO_ROTATE( side );
-
- bevel =
- FT_BOOL( stroker->line_join == FT_STROKER_LINEJOIN_BEVEL );
-
- fixed_bevel =
- FT_BOOL( stroker->line_join != FT_STROKER_LINEJOIN_MITER_VARIABLE );
-
- if ( !bevel )
- {
- theta = FT_Angle_Diff( stroker->angle_in, stroker->angle_out );
-
- if ( theta == FT_ANGLE_PI )
- {
- theta = rotate;
- phi = stroker->angle_in;
- }
- else
- {
- theta /= 2;
- phi = stroker->angle_in + theta + rotate;
- }
-
- thcos = FT_Cos( theta );
- sigma = FT_MulFix( stroker->miter_limit, thcos );
-
- /* is miter limit exceeded? */
- if ( sigma < 0x10000L )
- {
- /* don't create variable bevels for very small deviations; */
- /* FT_Sin(x) = 0 for x <= 57 */
- if ( fixed_bevel || ft_pos_abs( theta ) > 57 )
- bevel = TRUE;
- }
- }
-
- if ( bevel ) /* this is a bevel (broken angle) */
- {
- if ( fixed_bevel )
- {
- /* the outer corners are simply joined together */
- FT_Vector delta;
-
-
- /* add bevel */
- FT_Vector_From_Polar( &delta,
- radius,
- stroker->angle_out + rotate );
- delta.x += stroker->center.x;
- delta.y += stroker->center.y;
-
- border->movable = FALSE;
- error = ft_stroke_border_lineto( border, &delta, FALSE );
- }
- else /* variable bevel */
- {
- /* the miter is truncated */
- FT_Vector middle, delta;
- FT_Fixed length;
-
-
- /* compute middle point */
- FT_Vector_From_Polar( &middle,
- FT_MulFix( radius, stroker->miter_limit ),
- phi );
- middle.x += stroker->center.x;
- middle.y += stroker->center.y;
-
- /* compute first angle point */
- length = FT_MulDiv( radius, 0x10000L - sigma,
- ft_pos_abs( FT_Sin( theta ) ) );
-
- FT_Vector_From_Polar( &delta, length, phi + rotate );
- delta.x += middle.x;
- delta.y += middle.y;
-
- error = ft_stroke_border_lineto( border, &delta, FALSE );
- if ( error )
- goto Exit;
-
- /* compute second angle point */
- FT_Vector_From_Polar( &delta, length, phi - rotate );
- delta.x += middle.x;
- delta.y += middle.y;
-
- error = ft_stroke_border_lineto( border, &delta, FALSE );
- if ( error )
- goto Exit;
-
- /* finally, add an end point; only needed if not lineto */
- /* (line_length is zero for curves) */
- if ( line_length == 0 )
- {
- FT_Vector_From_Polar( &delta,
- radius,
- stroker->angle_out + rotate );
-
- delta.x += stroker->center.x;
- delta.y += stroker->center.y;
-
- error = ft_stroke_border_lineto( border, &delta, FALSE );
- }
- }
- }
- else /* this is a miter (intersection) */
- {
- FT_Fixed length;
- FT_Vector delta;
-
-
- length = FT_DivFix( stroker->radius, thcos );
-
- FT_Vector_From_Polar( &delta, length, phi );
- delta.x += stroker->center.x;
- delta.y += stroker->center.y;
-
- error = ft_stroke_border_lineto( border, &delta, FALSE );
- if ( error )
- goto Exit;
-
- /* now add an end point; only needed if not lineto */
- /* (line_length is zero for curves) */
- if ( line_length == 0 )
- {
- FT_Vector_From_Polar( &delta,
- stroker->radius,
- stroker->angle_out + rotate );
- delta.x += stroker->center.x;
- delta.y += stroker->center.y;
-
- error = ft_stroke_border_lineto( border, &delta, FALSE );
- }
- }
- }
-
- Exit:
- return error;
- }
-
-
- static FT_Error
- ft_stroker_process_corner( FT_Stroker stroker,
- FT_Fixed line_length )
- {
- FT_Error error = FT_Err_Ok;
- FT_Angle turn;
- FT_Int inside_side;
-
-
- turn = FT_Angle_Diff( stroker->angle_in, stroker->angle_out );
-
- /* no specific corner processing is required if the turn is 0 */
- if ( turn == 0 )
- goto Exit;
-
- /* when we turn to the right, the inside side is 0 */
- /* otherwise, the inside side is 1 */
- inside_side = ( turn < 0 );
-
- /* process the inside side */
- error = ft_stroker_inside( stroker, inside_side, line_length );
- if ( error )
- goto Exit;
-
- /* process the outside side */
- error = ft_stroker_outside( stroker, !inside_side, line_length );
-
- Exit:
- return error;
- }
-
-
- /* add two points to the left and right borders corresponding to the */
- /* start of the subpath */
- static FT_Error
- ft_stroker_subpath_start( FT_Stroker stroker,
- FT_Angle start_angle,
- FT_Fixed line_length )
- {
- FT_Vector delta;
- FT_Vector point;
- FT_Error error;
- FT_StrokeBorder border;
-
-
- FT_Vector_From_Polar( &delta, stroker->radius,
- start_angle + FT_ANGLE_PI2 );
-
- point.x = stroker->center.x + delta.x;
- point.y = stroker->center.y + delta.y;
-
- border = stroker->borders;
- error = ft_stroke_border_moveto( border, &point );
- if ( error )
- goto Exit;
-
- point.x = stroker->center.x - delta.x;
- point.y = stroker->center.y - delta.y;
-
- border++;
- error = ft_stroke_border_moveto( border, &point );
-
- /* save angle, position, and line length for last join */
- /* (line_length is zero for curves) */
- stroker->subpath_angle = start_angle;
- stroker->first_point = FALSE;
- stroker->subpath_line_length = line_length;
-
- Exit:
- return error;
- }
-
-
- /* documentation is in ftstroke.h */
-
- FT_EXPORT_DEF( FT_Error )
- FT_Stroker_LineTo( FT_Stroker stroker,
- FT_Vector* to )
- {
- FT_Error error = FT_Err_Ok;
- FT_StrokeBorder border;
- FT_Vector delta;
- FT_Angle angle;
- FT_Int side;
- FT_Fixed line_length;
-
-
- if ( !stroker || !to )
- return FT_THROW( Invalid_Argument );
-
- delta.x = to->x - stroker->center.x;
- delta.y = to->y - stroker->center.y;
-
- /* a zero-length lineto is a no-op; avoid creating a spurious corner */
- if ( delta.x == 0 && delta.y == 0 )
- goto Exit;
-
- /* compute length of line */
- line_length = FT_Vector_Length( &delta );
-
- angle = FT_Atan2( delta.x, delta.y );
- FT_Vector_From_Polar( &delta, stroker->radius, angle + FT_ANGLE_PI2 );
-
- /* process corner if necessary */
- if ( stroker->first_point )
- {
- /* This is the first segment of a subpath. We need to */
- /* add a point to each border at their respective starting */
- /* point locations. */
- error = ft_stroker_subpath_start( stroker, angle, line_length );
- if ( error )
- goto Exit;
- }
- else
- {
- /* process the current corner */
- stroker->angle_out = angle;
- error = ft_stroker_process_corner( stroker, line_length );
- if ( error )
- goto Exit;
- }
-
- /* now add a line segment to both the `inside' and `outside' paths */
- for ( border = stroker->borders, side = 1; side >= 0; side--, border++ )
- {
- FT_Vector point;
-
-
- point.x = to->x + delta.x;
- point.y = to->y + delta.y;
-
- /* the ends of lineto borders are movable */
- error = ft_stroke_border_lineto( border, &point, TRUE );
- if ( error )
- goto Exit;
-
- delta.x = -delta.x;
- delta.y = -delta.y;
- }
-
- stroker->angle_in = angle;
- stroker->center = *to;
- stroker->line_length = line_length;
-
- Exit:
- return error;
- }
-
-
- /* documentation is in ftstroke.h */
-
- FT_EXPORT_DEF( FT_Error )
- FT_Stroker_ConicTo( FT_Stroker stroker,
- FT_Vector* control,
- FT_Vector* to )
- {
- FT_Error error = FT_Err_Ok;
- FT_Vector bez_stack[34];
- FT_Vector* arc;
- FT_Vector* limit = bez_stack + 30;
- FT_Bool first_arc = TRUE;
-
-
- if ( !stroker || !control || !to )
- {
- error = FT_THROW( Invalid_Argument );
- goto Exit;
- }
-
- /* if all control points are coincident, this is a no-op; */
- /* avoid creating a spurious corner */
- if ( FT_IS_SMALL( stroker->center.x - control->x ) &&
- FT_IS_SMALL( stroker->center.y - control->y ) &&
- FT_IS_SMALL( control->x - to->x ) &&
- FT_IS_SMALL( control->y - to->y ) )
- {
- stroker->center = *to;
- goto Exit;
- }
-
- arc = bez_stack;
- arc[0] = *to;
- arc[1] = *control;
- arc[2] = stroker->center;
-
- while ( arc >= bez_stack )
- {
- FT_Angle angle_in, angle_out;
-
-
- /* initialize with current direction */
- angle_in = angle_out = stroker->angle_in;
-
- if ( arc < limit &&
- !ft_conic_is_small_enough( arc, &angle_in, &angle_out ) )
- {
- if ( stroker->first_point )
- stroker->angle_in = angle_in;
-
- ft_conic_split( arc );
- arc += 2;
- continue;
- }
-
- if ( first_arc )
- {
- first_arc = FALSE;
-
- /* process corner if necessary */
- if ( stroker->first_point )
- error = ft_stroker_subpath_start( stroker, angle_in, 0 );
- else
- {
- stroker->angle_out = angle_in;
- error = ft_stroker_process_corner( stroker, 0 );
- }
- }
- else if ( ft_pos_abs( FT_Angle_Diff( stroker->angle_in, angle_in ) ) >
- FT_SMALL_CONIC_THRESHOLD / 4 )
- {
- /* if the deviation from one arc to the next is too great, */
- /* add a round corner */
- stroker->center = arc[2];
- stroker->angle_out = angle_in;
- stroker->line_join = FT_STROKER_LINEJOIN_ROUND;
-
- error = ft_stroker_process_corner( stroker, 0 );
-
- /* reinstate line join style */
- stroker->line_join = stroker->line_join_saved;
- }
-
- if ( error )
- goto Exit;
-
- /* the arc's angle is small enough; we can add it directly to each */
- /* border */
- {
- FT_Vector ctrl, end;
- FT_Angle theta, phi, rotate, alpha0 = 0;
- FT_Fixed length;
- FT_StrokeBorder border;
- FT_Int side;
-
-
- theta = FT_Angle_Diff( angle_in, angle_out ) / 2;
- phi = angle_in + theta;
- length = FT_DivFix( stroker->radius, FT_Cos( theta ) );
-
- /* compute direction of original arc */
- if ( stroker->handle_wide_strokes )
- alpha0 = FT_Atan2( arc[0].x - arc[2].x, arc[0].y - arc[2].y );
-
- for ( border = stroker->borders, side = 0;
- side <= 1;
- side++, border++ )
- {
- rotate = FT_SIDE_TO_ROTATE( side );
-
- /* compute control point */
- FT_Vector_From_Polar( &ctrl, length, phi + rotate );
- ctrl.x += arc[1].x;
- ctrl.y += arc[1].y;
-
- /* compute end point */
- FT_Vector_From_Polar( &end, stroker->radius, angle_out + rotate );
- end.x += arc[0].x;
- end.y += arc[0].y;
-
- if ( stroker->handle_wide_strokes )
- {
- FT_Vector start;
- FT_Angle alpha1;
-
-
- /* determine whether the border radius is greater than the */
- /* radius of curvature of the original arc */
- start = border->points[border->num_points - 1];
-
- alpha1 = FT_Atan2( end.x - start.x, end.y - start.y );
-
- /* is the direction of the border arc opposite to */
- /* that of the original arc? */
- if ( ft_pos_abs( FT_Angle_Diff( alpha0, alpha1 ) ) >
- FT_ANGLE_PI / 2 )
- {
- FT_Angle beta, gamma;
- FT_Vector bvec, delta;
- FT_Fixed blen, sinA, sinB, alen;
-
-
- /* use the sine rule to find the intersection point */
- beta = FT_Atan2( arc[2].x - start.x, arc[2].y - start.y );
- gamma = FT_Atan2( arc[0].x - end.x, arc[0].y - end.y );
-
- bvec.x = end.x - start.x;
- bvec.y = end.y - start.y;
-
- blen = FT_Vector_Length( &bvec );
-
- sinA = ft_pos_abs( FT_Sin( alpha1 - gamma ) );
- sinB = ft_pos_abs( FT_Sin( beta - gamma ) );
-
- alen = FT_MulDiv( blen, sinA, sinB );
-
- FT_Vector_From_Polar( &delta, alen, beta );
- delta.x += start.x;
- delta.y += start.y;
-
- /* circumnavigate the negative sector backwards */
- border->movable = FALSE;
- error = ft_stroke_border_lineto( border, &delta, FALSE );
- if ( error )
- goto Exit;
- error = ft_stroke_border_lineto( border, &end, FALSE );
- if ( error )
- goto Exit;
- error = ft_stroke_border_conicto( border, &ctrl, &start );
- if ( error )
- goto Exit;
- /* and then move to the endpoint */
- error = ft_stroke_border_lineto( border, &end, FALSE );
- if ( error )
- goto Exit;
-
- continue;
- }
-
- /* else fall through */
- }
-
- /* simply add an arc */
- error = ft_stroke_border_conicto( border, &ctrl, &end );
- if ( error )
- goto Exit;
- }
- }
-
- arc -= 2;
-
- stroker->angle_in = angle_out;
- }
-
- stroker->center = *to;
-
- Exit:
- return error;
- }
-
-
- /* documentation is in ftstroke.h */
-
- FT_EXPORT_DEF( FT_Error )
- FT_Stroker_CubicTo( FT_Stroker stroker,
- FT_Vector* control1,
- FT_Vector* control2,
- FT_Vector* to )
- {
- FT_Error error = FT_Err_Ok;
- FT_Vector bez_stack[37];
- FT_Vector* arc;
- FT_Vector* limit = bez_stack + 32;
- FT_Bool first_arc = TRUE;
-
-
- if ( !stroker || !control1 || !control2 || !to )
- {
- error = FT_THROW( Invalid_Argument );
- goto Exit;
- }
-
- /* if all control points are coincident, this is a no-op; */
- /* avoid creating a spurious corner */
- if ( FT_IS_SMALL( stroker->center.x - control1->x ) &&
- FT_IS_SMALL( stroker->center.y - control1->y ) &&
- FT_IS_SMALL( control1->x - control2->x ) &&
- FT_IS_SMALL( control1->y - control2->y ) &&
- FT_IS_SMALL( control2->x - to->x ) &&
- FT_IS_SMALL( control2->y - to->y ) )
- {
- stroker->center = *to;
- goto Exit;
- }
-
- arc = bez_stack;
- arc[0] = *to;
- arc[1] = *control2;
- arc[2] = *control1;
- arc[3] = stroker->center;
-
- while ( arc >= bez_stack )
- {
- FT_Angle angle_in, angle_mid, angle_out;
-
-
- /* initialize with current direction */
- angle_in = angle_out = angle_mid = stroker->angle_in;
-
- if ( arc < limit &&
- !ft_cubic_is_small_enough( arc, &angle_in,
- &angle_mid, &angle_out ) )
- {
- if ( stroker->first_point )
- stroker->angle_in = angle_in;
-
- ft_cubic_split( arc );
- arc += 3;
- continue;
- }
-
- if ( first_arc )
- {
- first_arc = FALSE;
-
- /* process corner if necessary */
- if ( stroker->first_point )
- error = ft_stroker_subpath_start( stroker, angle_in, 0 );
- else
- {
- stroker->angle_out = angle_in;
- error = ft_stroker_process_corner( stroker, 0 );
- }
- }
- else if ( ft_pos_abs( FT_Angle_Diff( stroker->angle_in, angle_in ) ) >
- FT_SMALL_CUBIC_THRESHOLD / 4 )
- {
- /* if the deviation from one arc to the next is too great, */
- /* add a round corner */
- stroker->center = arc[3];
- stroker->angle_out = angle_in;
- stroker->line_join = FT_STROKER_LINEJOIN_ROUND;
-
- error = ft_stroker_process_corner( stroker, 0 );
-
- /* reinstate line join style */
- stroker->line_join = stroker->line_join_saved;
- }
-
- if ( error )
- goto Exit;
-
- /* the arc's angle is small enough; we can add it directly to each */
- /* border */
- {
- FT_Vector ctrl1, ctrl2, end;
- FT_Angle theta1, phi1, theta2, phi2, rotate, alpha0 = 0;
- FT_Fixed length1, length2;
- FT_StrokeBorder border;
- FT_Int side;
-
-
- theta1 = FT_Angle_Diff( angle_in, angle_mid ) / 2;
- theta2 = FT_Angle_Diff( angle_mid, angle_out ) / 2;
- phi1 = ft_angle_mean( angle_in, angle_mid );
- phi2 = ft_angle_mean( angle_mid, angle_out );
- length1 = FT_DivFix( stroker->radius, FT_Cos( theta1 ) );
- length2 = FT_DivFix( stroker->radius, FT_Cos( theta2 ) );
-
- /* compute direction of original arc */
- if ( stroker->handle_wide_strokes )
- alpha0 = FT_Atan2( arc[0].x - arc[3].x, arc[0].y - arc[3].y );
-
- for ( border = stroker->borders, side = 0;
- side <= 1;
- side++, border++ )
- {
- rotate = FT_SIDE_TO_ROTATE( side );
-
- /* compute control points */
- FT_Vector_From_Polar( &ctrl1, length1, phi1 + rotate );
- ctrl1.x += arc[2].x;
- ctrl1.y += arc[2].y;
-
- FT_Vector_From_Polar( &ctrl2, length2, phi2 + rotate );
- ctrl2.x += arc[1].x;
- ctrl2.y += arc[1].y;
-
- /* compute end point */
- FT_Vector_From_Polar( &end, stroker->radius, angle_out + rotate );
- end.x += arc[0].x;
- end.y += arc[0].y;
-
- if ( stroker->handle_wide_strokes )
- {
- FT_Vector start;
- FT_Angle alpha1;
-
-
- /* determine whether the border radius is greater than the */
- /* radius of curvature of the original arc */
- start = border->points[border->num_points - 1];
-
- alpha1 = FT_Atan2( end.x - start.x, end.y - start.y );
-
- /* is the direction of the border arc opposite to */
- /* that of the original arc? */
- if ( ft_pos_abs( FT_Angle_Diff( alpha0, alpha1 ) ) >
- FT_ANGLE_PI / 2 )
- {
- FT_Angle beta, gamma;
- FT_Vector bvec, delta;
- FT_Fixed blen, sinA, sinB, alen;
-
-
- /* use the sine rule to find the intersection point */
- beta = FT_Atan2( arc[3].x - start.x, arc[3].y - start.y );
- gamma = FT_Atan2( arc[0].x - end.x, arc[0].y - end.y );
-
- bvec.x = end.x - start.x;
- bvec.y = end.y - start.y;
-
- blen = FT_Vector_Length( &bvec );
-
- sinA = ft_pos_abs( FT_Sin( alpha1 - gamma ) );
- sinB = ft_pos_abs( FT_Sin( beta - gamma ) );
-
- alen = FT_MulDiv( blen, sinA, sinB );
-
- FT_Vector_From_Polar( &delta, alen, beta );
- delta.x += start.x;
- delta.y += start.y;
-
- /* circumnavigate the negative sector backwards */
- border->movable = FALSE;
- error = ft_stroke_border_lineto( border, &delta, FALSE );
- if ( error )
- goto Exit;
- error = ft_stroke_border_lineto( border, &end, FALSE );
- if ( error )
- goto Exit;
- error = ft_stroke_border_cubicto( border,
- &ctrl2,
- &ctrl1,
- &start );
- if ( error )
- goto Exit;
- /* and then move to the endpoint */
- error = ft_stroke_border_lineto( border, &end, FALSE );
- if ( error )
- goto Exit;
-
- continue;
- }
-
- /* else fall through */
- }
-
- /* simply add an arc */
- error = ft_stroke_border_cubicto( border, &ctrl1, &ctrl2, &end );
- if ( error )
- goto Exit;
- }
- }
-
- arc -= 3;
-
- stroker->angle_in = angle_out;
- }
-
- stroker->center = *to;
-
- Exit:
- return error;
- }
-
-
- /* documentation is in ftstroke.h */
-
- FT_EXPORT_DEF( FT_Error )
- FT_Stroker_BeginSubPath( FT_Stroker stroker,
- FT_Vector* to,
- FT_Bool open )
- {
- if ( !stroker || !to )
- return FT_THROW( Invalid_Argument );
-
- /* We cannot process the first point, because there is not enough */
- /* information regarding its corner/cap. The latter will be processed */
- /* in the `FT_Stroker_EndSubPath' routine. */
- /* */
- stroker->first_point = TRUE;
- stroker->center = *to;
- stroker->subpath_open = open;
-
- /* Determine if we need to check whether the border radius is greater */
- /* than the radius of curvature of a curve, to handle this case */
- /* specially. This is only required if bevel joins or butt caps may */
- /* be created, because round & miter joins and round & square caps */
- /* cover the negative sector created with wide strokes. */
- stroker->handle_wide_strokes =
- FT_BOOL( stroker->line_join != FT_STROKER_LINEJOIN_ROUND ||
- ( stroker->subpath_open &&
- stroker->line_cap == FT_STROKER_LINECAP_BUTT ) );
-
- /* record the subpath start point for each border */
- stroker->subpath_start = *to;
-
- stroker->angle_in = 0;
-
- return FT_Err_Ok;
- }
-
-
- static FT_Error
- ft_stroker_add_reverse_left( FT_Stroker stroker,
- FT_Bool open )
- {
- FT_StrokeBorder right = stroker->borders + 0;
- FT_StrokeBorder left = stroker->borders + 1;
- FT_Int new_points;
- FT_Error error = FT_Err_Ok;
-
-
- FT_ASSERT( left->start >= 0 );
-
- new_points = (FT_Int)left->num_points - left->start;
- if ( new_points > 0 )
- {
- error = ft_stroke_border_grow( right, (FT_UInt)new_points );
- if ( error )
- goto Exit;
-
- {
- FT_Vector* dst_point = right->points + right->num_points;
- FT_Byte* dst_tag = right->tags + right->num_points;
- FT_Vector* src_point = left->points + left->num_points - 1;
- FT_Byte* src_tag = left->tags + left->num_points - 1;
-
-
- while ( src_point >= left->points + left->start )
- {
- *dst_point = *src_point;
- *dst_tag = *src_tag;
-
- if ( open )
- dst_tag[0] &= ~FT_STROKE_TAG_BEGIN_END;
- else
- {
- FT_Byte ttag =
- (FT_Byte)( dst_tag[0] & FT_STROKE_TAG_BEGIN_END );
-
-
- /* switch begin/end tags if necessary */
- if ( ttag == FT_STROKE_TAG_BEGIN ||
- ttag == FT_STROKE_TAG_END )
- dst_tag[0] ^= FT_STROKE_TAG_BEGIN_END;
- }
-
- src_point--;
- src_tag--;
- dst_point++;
- dst_tag++;
- }
- }
-
- left->num_points = (FT_UInt)left->start;
- right->num_points += (FT_UInt)new_points;
-
- right->movable = FALSE;
- left->movable = FALSE;
- }
-
- Exit:
- return error;
- }
-
-
- /* documentation is in ftstroke.h */
-
- /* there's a lot of magic in this function! */
- FT_EXPORT_DEF( FT_Error )
- FT_Stroker_EndSubPath( FT_Stroker stroker )
- {
- FT_Error error = FT_Err_Ok;
-
-
- if ( !stroker )
- {
- error = FT_THROW( Invalid_Argument );
- goto Exit;
- }
-
- if ( stroker->subpath_open )
- {
- FT_StrokeBorder right = stroker->borders;
-
-
- /* All right, this is an opened path, we need to add a cap between */
- /* right & left, add the reverse of left, then add a final cap */
- /* between left & right. */
- error = ft_stroker_cap( stroker, stroker->angle_in, 0 );
- if ( error )
- goto Exit;
-
- /* add reversed points from `left' to `right' */
- error = ft_stroker_add_reverse_left( stroker, TRUE );
- if ( error )
- goto Exit;
-
- /* now add the final cap */
- stroker->center = stroker->subpath_start;
- error = ft_stroker_cap( stroker,
- stroker->subpath_angle + FT_ANGLE_PI, 0 );
- if ( error )
- goto Exit;
-
- /* Now end the right subpath accordingly. The left one is */
- /* rewind and doesn't need further processing. */
- ft_stroke_border_close( right, FALSE );
- }
- else
- {
- FT_Angle turn;
- FT_Int inside_side;
-
-
- /* close the path if needed */
- if ( stroker->center.x != stroker->subpath_start.x ||
- stroker->center.y != stroker->subpath_start.y )
- {
- error = FT_Stroker_LineTo( stroker, &stroker->subpath_start );
- if ( error )
- goto Exit;
- }
-
- /* process the corner */
- stroker->angle_out = stroker->subpath_angle;
- turn = FT_Angle_Diff( stroker->angle_in,
- stroker->angle_out );
-
- /* no specific corner processing is required if the turn is 0 */
- if ( turn != 0 )
- {
- /* when we turn to the right, the inside side is 0 */
- /* otherwise, the inside side is 1 */
- inside_side = ( turn < 0 );
-
- error = ft_stroker_inside( stroker,
- inside_side,
- stroker->subpath_line_length );
- if ( error )
- goto Exit;
-
- /* process the outside side */
- error = ft_stroker_outside( stroker,
- !inside_side,
- stroker->subpath_line_length );
- if ( error )
- goto Exit;
- }
-
- /* then end our two subpaths */
- ft_stroke_border_close( stroker->borders + 0, FALSE );
- ft_stroke_border_close( stroker->borders + 1, TRUE );
- }
-
- Exit:
- return error;
- }
-
-
- /* documentation is in ftstroke.h */
-
- FT_EXPORT_DEF( FT_Error )
- FT_Stroker_GetBorderCounts( FT_Stroker stroker,
- FT_StrokerBorder border,
- FT_UInt *anum_points,
- FT_UInt *anum_contours )
- {
- FT_UInt num_points = 0, num_contours = 0;
- FT_Error error;
-
-
- if ( !stroker || border > 1 )
- {
- error = FT_THROW( Invalid_Argument );
- goto Exit;
- }
-
- error = ft_stroke_border_get_counts( stroker->borders + border,
- &num_points, &num_contours );
- Exit:
- if ( anum_points )
- *anum_points = num_points;
-
- if ( anum_contours )
- *anum_contours = num_contours;
-
- return error;
- }
-
-
- /* documentation is in ftstroke.h */
-
- FT_EXPORT_DEF( FT_Error )
- FT_Stroker_GetCounts( FT_Stroker stroker,
- FT_UInt *anum_points,
- FT_UInt *anum_contours )
- {
- FT_UInt count1, count2, num_points = 0;
- FT_UInt count3, count4, num_contours = 0;
- FT_Error error;
-
-
- if ( !stroker )
- {
- error = FT_THROW( Invalid_Argument );
- goto Exit;
- }
-
- error = ft_stroke_border_get_counts( stroker->borders + 0,
- &count1, &count2 );
- if ( error )
- goto Exit;
-
- error = ft_stroke_border_get_counts( stroker->borders + 1,
- &count3, &count4 );
- if ( error )
- goto Exit;
-
- num_points = count1 + count3;
- num_contours = count2 + count4;
-
- Exit:
- if ( anum_points )
- *anum_points = num_points;
-
- if ( anum_contours )
- *anum_contours = num_contours;
-
- return error;
- }
-
-
- /* documentation is in ftstroke.h */
-
- FT_EXPORT_DEF( void )
- FT_Stroker_ExportBorder( FT_Stroker stroker,
- FT_StrokerBorder border,
- FT_Outline* outline )
- {
- if ( !stroker || !outline )
- return;
-
- if ( border == FT_STROKER_BORDER_LEFT ||
- border == FT_STROKER_BORDER_RIGHT )
- {
- FT_StrokeBorder sborder = & stroker->borders[border];
-
-
- if ( sborder->valid )
- ft_stroke_border_export( sborder, outline );
- }
- }
-
-
- /* documentation is in ftstroke.h */
-
- FT_EXPORT_DEF( void )
- FT_Stroker_Export( FT_Stroker stroker,
- FT_Outline* outline )
- {
- FT_Stroker_ExportBorder( stroker, FT_STROKER_BORDER_LEFT, outline );
- FT_Stroker_ExportBorder( stroker, FT_STROKER_BORDER_RIGHT, outline );
- }
-
-
- /* documentation is in ftstroke.h */
-
- /*
- * The following is very similar to FT_Outline_Decompose, except
- * that we do support opened paths, and do not scale the outline.
- */
- FT_EXPORT_DEF( FT_Error )
- FT_Stroker_ParseOutline( FT_Stroker stroker,
- FT_Outline* outline,
- FT_Bool opened )
- {
- FT_Vector v_last;
- FT_Vector v_control;
- FT_Vector v_start;
-
- FT_Vector* point;
- FT_Vector* limit;
- char* tags;
-
- FT_Error error;
-
- FT_Int n; /* index of contour in outline */
- FT_UInt first; /* index of first point in contour */
- FT_Int tag; /* current point's state */
-
-
- if ( !outline )
- return FT_THROW( Invalid_Outline );
-
- if ( !stroker )
- return FT_THROW( Invalid_Argument );
-
- FT_Stroker_Rewind( stroker );
-
- first = 0;
-
- for ( n = 0; n < outline->n_contours; n++ )
- {
- FT_UInt last; /* index of last point in contour */
-
-
- last = (FT_UInt)outline->contours[n];
- limit = outline->points + last;
-
- /* skip empty points; we don't stroke these */
- if ( last <= first )
- {
- first = last + 1;
- continue;
- }
-
- v_start = outline->points[first];
- v_last = outline->points[last];
-
- v_control = v_start;
-
- point = outline->points + first;
- tags = outline->tags + first;
- tag = FT_CURVE_TAG( tags[0] );
-
- /* A contour cannot start with a cubic control point! */
- if ( tag == FT_CURVE_TAG_CUBIC )
- goto Invalid_Outline;
-
- /* check first point to determine origin */
- if ( tag == FT_CURVE_TAG_CONIC )
- {
- /* First point is conic control. Yes, this happens. */
- if ( FT_CURVE_TAG( outline->tags[last] ) == FT_CURVE_TAG_ON )
- {
- /* start at last point if it is on the curve */
- v_start = v_last;
- limit--;
- }
- else
- {
- /* if both first and last points are conic, */
- /* start at their middle */
- v_start.x = ( v_start.x + v_last.x ) / 2;
- v_start.y = ( v_start.y + v_last.y ) / 2;
- }
- point--;
- tags--;
- }
-
- error = FT_Stroker_BeginSubPath( stroker, &v_start, opened );
- if ( error )
- goto Exit;
-
- while ( point < limit )
- {
- point++;
- tags++;
-
- tag = FT_CURVE_TAG( tags[0] );
- switch ( tag )
- {
- case FT_CURVE_TAG_ON: /* emit a single line_to */
- {
- FT_Vector vec;
-
-
- vec.x = point->x;
- vec.y = point->y;
-
- error = FT_Stroker_LineTo( stroker, &vec );
- if ( error )
- goto Exit;
- continue;
- }
-
- case FT_CURVE_TAG_CONIC: /* consume conic arcs */
- v_control.x = point->x;
- v_control.y = point->y;
-
- Do_Conic:
- if ( point < limit )
- {
- FT_Vector vec;
- FT_Vector v_middle;
-
-
- point++;
- tags++;
- tag = FT_CURVE_TAG( tags[0] );
-
- vec = point[0];
-
- if ( tag == FT_CURVE_TAG_ON )
- {
- error = FT_Stroker_ConicTo( stroker, &v_control, &vec );
- if ( error )
- goto Exit;
- continue;
- }
-
- if ( tag != FT_CURVE_TAG_CONIC )
- goto Invalid_Outline;
-
- v_middle.x = ( v_control.x + vec.x ) / 2;
- v_middle.y = ( v_control.y + vec.y ) / 2;
-
- error = FT_Stroker_ConicTo( stroker, &v_control, &v_middle );
- if ( error )
- goto Exit;
-
- v_control = vec;
- goto Do_Conic;
- }
-
- error = FT_Stroker_ConicTo( stroker, &v_control, &v_start );
- goto Close;
-
- default: /* FT_CURVE_TAG_CUBIC */
- {
- FT_Vector vec1, vec2;
-
-
- if ( point + 1 > limit ||
- FT_CURVE_TAG( tags[1] ) != FT_CURVE_TAG_CUBIC )
- goto Invalid_Outline;
-
- point += 2;
- tags += 2;
-
- vec1 = point[-2];
- vec2 = point[-1];
-
- if ( point <= limit )
- {
- FT_Vector vec;
-
-
- vec = point[0];
-
- error = FT_Stroker_CubicTo( stroker, &vec1, &vec2, &vec );
- if ( error )
- goto Exit;
- continue;
- }
-
- error = FT_Stroker_CubicTo( stroker, &vec1, &vec2, &v_start );
- goto Close;
- }
- }
- }
-
- Close:
- if ( error )
- goto Exit;
-
- /* don't try to end the path if no segments have been generated */
- if ( !stroker->first_point )
- {
- error = FT_Stroker_EndSubPath( stroker );
- if ( error )
- goto Exit;
- }
-
- first = last + 1;
- }
-
- return FT_Err_Ok;
-
- Exit:
- return error;
-
- Invalid_Outline:
- return FT_THROW( Invalid_Outline );
- }
-
-
- /* documentation is in ftstroke.h */
-
- FT_EXPORT_DEF( FT_Error )
- FT_Glyph_Stroke( FT_Glyph *pglyph,
- FT_Stroker stroker,
- FT_Bool destroy )
- {
- FT_Error error = FT_ERR( Invalid_Argument );
- FT_Glyph glyph = NULL;
-
- /* for FT_OUTLINE_GLYPH_CLASS_GET (in PIC mode) */
- FT_Library library = stroker->library;
-
- FT_UNUSED( library );
-
-
- if ( !pglyph )
- goto Exit;
-
- glyph = *pglyph;
- if ( !glyph || glyph->clazz != FT_OUTLINE_GLYPH_CLASS_GET )
- goto Exit;
-
- {
- FT_Glyph copy;
-
-
- error = FT_Glyph_Copy( glyph, © );
- if ( error )
- goto Exit;
-
- glyph = copy;
- }
-
- {
- FT_OutlineGlyph oglyph = (FT_OutlineGlyph)glyph;
- FT_Outline* outline = &oglyph->outline;
- FT_UInt num_points, num_contours;
-
-
- error = FT_Stroker_ParseOutline( stroker, outline, FALSE );
- if ( error )
- goto Fail;
-
- FT_Stroker_GetCounts( stroker, &num_points, &num_contours );
-
- FT_Outline_Done( glyph->library, outline );
-
- error = FT_Outline_New( glyph->library,
- num_points,
- (FT_Int)num_contours,
- outline );
- if ( error )
- goto Fail;
-
- outline->n_points = 0;
- outline->n_contours = 0;
-
- FT_Stroker_Export( stroker, outline );
- }
-
- if ( destroy )
- FT_Done_Glyph( *pglyph );
-
- *pglyph = glyph;
- goto Exit;
-
- Fail:
- FT_Done_Glyph( glyph );
- glyph = NULL;
-
- if ( !destroy )
- *pglyph = NULL;
-
- Exit:
- return error;
- }
-
-
- /* documentation is in ftstroke.h */
-
- FT_EXPORT_DEF( FT_Error )
- FT_Glyph_StrokeBorder( FT_Glyph *pglyph,
- FT_Stroker stroker,
- FT_Bool inside,
- FT_Bool destroy )
- {
- FT_Error error = FT_ERR( Invalid_Argument );
- FT_Glyph glyph = NULL;
-
- /* for FT_OUTLINE_GLYPH_CLASS_GET (in PIC mode) */
- FT_Library library = stroker->library;
-
- FT_UNUSED( library );
-
-
- if ( !pglyph )
- goto Exit;
-
- glyph = *pglyph;
- if ( !glyph || glyph->clazz != FT_OUTLINE_GLYPH_CLASS_GET )
- goto Exit;
-
- {
- FT_Glyph copy;
-
-
- error = FT_Glyph_Copy( glyph, © );
- if ( error )
- goto Exit;
-
- glyph = copy;
- }
-
- {
- FT_OutlineGlyph oglyph = (FT_OutlineGlyph)glyph;
- FT_StrokerBorder border;
- FT_Outline* outline = &oglyph->outline;
- FT_UInt num_points, num_contours;
-
-
- border = FT_Outline_GetOutsideBorder( outline );
- if ( inside )
- {
- if ( border == FT_STROKER_BORDER_LEFT )
- border = FT_STROKER_BORDER_RIGHT;
- else
- border = FT_STROKER_BORDER_LEFT;
- }
-
- error = FT_Stroker_ParseOutline( stroker, outline, FALSE );
- if ( error )
- goto Fail;
-
- FT_Stroker_GetBorderCounts( stroker, border,
- &num_points, &num_contours );
-
- FT_Outline_Done( glyph->library, outline );
-
- error = FT_Outline_New( glyph->library,
- num_points,
- (FT_Int)num_contours,
- outline );
- if ( error )
- goto Fail;
-
- outline->n_points = 0;
- outline->n_contours = 0;
-
- FT_Stroker_ExportBorder( stroker, border, outline );
- }
-
- if ( destroy )
- FT_Done_Glyph( *pglyph );
-
- *pglyph = glyph;
- goto Exit;
-
- Fail:
- FT_Done_Glyph( glyph );
- glyph = NULL;
-
- if ( !destroy )
- *pglyph = NULL;
-
- Exit:
- return error;
- }
-
-
-/* END */
projects / reactos.git / blobdiff